I looked for images of a nice sunlit ISS crew cabin interior and predictably didn't have much luck. Most hits were mentions of the sunlight the astronaut would leave behind on earth, or enjoy again after returning.
But I found a few images of astronauts (possibly) enjoying some sunshine. I found one interior photo of Terry Virts with sunshine on his face, and a few exterior shots of Andre Kuipers, Paolo Nespoli and a group shot of Alexander Gerst, Reid Wiseman and Max Suraev, looking out through a cupola window with sunlit faces. Paolo Nespoli is shielding his eyes from direct sunlight, and it looks like Andre Kuipers is wearing sunglasses??
above: TOP: Andre Kuipers, Exp. 30, BOTTOM: Paolo Nespoli, cropped/enlarged from image below.
I can imagine there are a number of reasons why the cupola windows would generally be set to block the sun, so letting sunshine into the crew area may be limited or discouraged, but I'm wondering if astronauts sometimes feel like opening the shades and letting natural light in at least once in a while.
Question: Do ISS astronauts occasionally let the sunshine in for a natural light "fix" - in other words to get a refreshing few minutes in natural lighting for a change? If so, are there limitations or restrictions associated with doing so?
above: ISS042e016586 (11/26/2014) --- NASA astronaut Terry Virts in the International Space Station on Earth sunrise Nov. 26, 2014 looks through the cupola window while checking the "dosimeter". The cupola allows the crew 360 degree vision around the station for both photos and operating the Canada arm to pull spacecraft up to the station ports. From here.
above: European Space Agency astronaut Andre Kuipers, Expedition 30 flight engineer, is pictured in a window of the Cupola of the International Space Station, backdropped by the blackness of space. ISS030-E-270550 (21 April 2012). From here.
above: Paolo Nespoli in the Cupola of the International Space Station. It has seven windows and provides a pressurized observation and work area for astronauts, according to the European Space Agency. From here
above: (From left) Expedition 40/41 crew members Alexander Gerst, Reid Wiseman and Max Suraev peer out of the cupola. From here.